Steam in Distribution and Use: Steam Quality Redefined

Abstract

Steam quality is an important measurement in steam generation. It's a measurement of steam to moisture ratio. In use, steam quality takes on a different meaning- steam which maximizes energy transfer. To do this, the steam must be clean, dry, of desired pressure and free of air and non-condensible gases. Objectives in these areas should be set and an action plan implemented. Typical objectives could be to specify steam pressure delivery of maximum pressure and to use steam at the lowest pressure possible. Steam velocity ranges and maximum system pressure drops should be set. Cleaning steam and protecting control devices is an important means of maintaining quality. Draining condensate and venting air and other gases preserves the steam quality at the point of use. Poor pressure control yields poor operation and efficiency. Dirty steam causes valve leaks and maintenance problems. Improper drainage and venting can cause premature corrosion and poor heat transfer.